1. Field of the Invention
The present invention relates in general to laundry washing appliances, such as laundry washers or combined laundry washers and dryers. The term “laundry” is here intended to include clothes and garments. In particular, the present invention relates to a laundry washing appliance having an auto-dosing dispensing arrangement for the laundry washing treatment liquids (e.g., detergents, softeners and the like).
2. Description of the Related Art
Laundry washing appliances like laundry washers and combined washers and dryers make use of laundry washing treatment products in the laundry washing cycle; such treatment products include for example detergents and softeners.
The laundry washing appliances generally include receptacles for the laundry treatment products, for example in the form of drawers provided in the appliance cabinet, from where, during the laundry washing cycle, the treatment products are taken and dispensed into the washing tub.
In recent years, the trend has been towards using liquid treatments products, instead of powder ones as in past years. However, the solutions for dispensing the laundry treatment products into the washing tub remained essentially unchanged, despite the evolution in the treatment products typologies and composition, and despite the reductions in the water consumption of the laundry washing appliances.
Auto-dosing dispensing of laundry treatment products to be used during a washing cycle is believed to be advantageous in several respects. For example, it would translate into a reduction of time and efforts of the users, which would be levied from the burden of dosing the correct amount of laundry treatment products, and would beneficially reflect on the environment pollution, because wastes would be reduced or eliminated.
Auto-dosing dispensing of the treatment products in liquid form has proved to be far easier compared to powder products. However, known treatment products dispensing systems are not suitable for liquid treatment products.
EP 1690972 discloses a softener-dosing container for electrical household appliances, having an upper casing positioned above the mixing compartment or drawer wherein the cleaning products are introduced. The dispensing reservoir comprises a watertight, hermetically sealed tray of large capacity, partially or totally removable with respect to a cavity defined in the upper casing and it has a drain hole for the passage of fabric softener to the drawer with the intermediation of a gear pump, in addition to incorporating a portion adjacent to the tray which forms part of the casing which includes electrical components to operate a motor which, through a transmission and by means of magnetized plates, determines the rotation of the pump positioned in the removable tray to push the fabric softener to the drawer. The body of the pump has an outlet gasket equipped with a discharge opening to push the fabric softener to the mixing compartment or drawer; a non-return valve is provided in correspondence with the discharge opening consisting of a sphere pressed by a spring which covers the discharge opening or leaves free passage for the discharge of the fabric softener once the spring pressure is exceeded.